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ATM Forum/98-0411

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Title: Proposed text for Performance Testing Terminology


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Abstract: This contribution provides the text for Performance
Testing Terminology.


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Source:
Arian Durresi, Gojko Babic, Raj Jain
The Ohio State University
Department of CIS Columbus, OH 43210-1277
Phone: 614-292-3989, Fax: 614-292-2911, Email: Jain@ACM.Org
The presentation of this contribution at the ATM Forum is
sponsored by NASA.

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Date: Portland, July 26-31, 1998

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Distribution: ATM Forum Technical Working Group Members (AF-TEST,
AF-TM)


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Notice:
This  contribution has been prepared to assist the ATM Forum.  It
is  offered to the Forum as a basis for discussion and is  not  a
binding   proposal  on  the  part  of  any  of  the  contributing
organizations. The statements are subject to change in  form  and
content  after  further  study.  Specifically,  the  contributors
reserve  the  right  to  add to, amend or modify  the  statements
contained herein.

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In  the  March ‘98 interim meeting of ATM Forum TEST and  TM
working  at  Columbus, Ohio, it was decided  to  generate  a
terminology section for performance testing. The purpose  of
this contribution is to provide the terminology section  for
the current baseline draft [1].


Motion:  Replace Section 1.4 of the current  baseline  draft
[1] by the remaining text of this contribution


ATM Interface - ATM physical interface where the ATM traffic
           enters and/or leaves the switch.

ATM connection   -   An  ATM  connection  consists  of   the
             concatenation of ATM layer links  in  order  to
             provide  an  end-to-end transfer capability  to
             access point [from I.150].

ATM Analyzer  -  ATM measuring equipment used to measure the
           characteristics of traffic received from SUT

ATM Generator  -  ATM  measuring equipment used  to  produce
             traffic with specified characteristics

Background Traffic  - Traffic made up of cells whose purpose
               is  to  load the SUT at an appropriate  level
               but the performance of these cells is not  of
               primary interest.

Background  connection  -  An ATM  connection  that  carries
background traffic.

Connection Load  -  Precisely  defined  specification  of  a
             pattern  of  ATM  cells and gaps  between  them
             over  a single connection; When cells are parts
             of  frames, a connection load may be defined in
             term   frame   pattern  and  inter-frame   gaps
             distribution.

Foreground Traffic  -  Traffic  made up of cells  or  frames
               whose performance is being measured.

Foreground  connection  -  An ATM  connection  that  carries
foreground traffic

Frame -   A   sequence  of  cells  produced   by   AAL   SAR
      (Segmentation and Reassembly) sublayer  as  result  of
      segmentation of one SDU from AAL Convergence sublayer

Frame Pattern - Precisely defined pattern of cells and intra-
          frame  gaps, inter-frame gaps, and frame sizes.  A
          frame  pattern  can  be defined  statistically  in
          terms  of  distributions of  frame  sizes,  inter-
          frame gaps, and intra-frame gaps.

Frame Size - Number of cells in a frame.

Input ATM Interface   Rate   -  Maximum  nominal   rate   in
                  cells/second  at which the  cells  can  be
                  received at the interface.

Inter-frame Gap  - time between transmission of the last bit
            of  the last cell one frame and transmission  of
            the  first  bit of the first cell  of  the  next
            frame.

Interface Load - Set of Connection Loads applied to an Input
ATM Interface.

Intra-frame Gap  - Time between transmission of the last bit
            of  one  cell and transmission of the first  bit
            of the next cell of the same frame.

Loopback  -  An external connection that connects the output
        and input of the same ATM interface.

Measurement point - See I.353.

Metric  -  A quantitative measure of the goodness of overall
      service  offered  by  a SUT, for example,  throughput,
      throughput fairness.


Monitor - same as ATM measuring equipment.


Network module  -  A  group  of  switch ATM interfaces  that
             physically reside on a single card.

Output ATM Interface   Rate   -  Maximum  nominal  rate   in
                    cells/second at which the cells  can  be
                    transmitted from the interface.

Parameter  -  A  quantitative  measure of  the  goodness  of
        services  received  by  a connection,  for  example,
        cell transfer delay, cell delay variation.

Port - same as ATM Interface.

Reference Load - Set of Interface Loads applied to SUT.

Scalable configuration - Configuration that permits to  load
                 the  SUT  using  a minimal  number  of  ATM
                 monitors.

Switch Fabric  - The switch component whose main function is
           to  transfer  cells among various  interfaces  of
           the switch.

System Under Test (SUT)  -  Any  collection of ATM equipment
                    that  is  being tested.  It could  be  a
                    single  switch  or  a  network  of   ATM
                    switches.

Traffic  Load - Connection Load, Interface Load or Reference
Load

Wire -  The physical medium used for external connections of
     the  SUT's  ATM interfaces. The medium could be  copper
     cables, optical fibers, or wireless links.




References:

1. ATM Forum/BTD-TEST-TM-PERF.00.07 (Draft)